Within the region of Northern California, in the United States, surrounded by the major cities of San Jose, San Francisco and Oakland, is the sprawling San Francisco Bay, a shallow estuary that is home to such famous landmarks as the island prison of Alcatraz and the Golden Gate Bridge, but it is also supposedly home to some sort of unidentified creature which has long been sighted and which remains and enigma. Sightings of something strange gliding through the waters of San Francisco Bay go all the way back to the 1800s, and some of the earliest reports were given in the October 31, 1875 edition of the Daily Alta. In one account, a ferry ticket taker at Long Wharf by the name of Colonel J. W. Wood claimed that he had seen a sea serpent near Long Bridge, of which he would say:

It was about one third of a mile north from the center of Long Bridge (a structure now covered with landfill and buildings), and appeared to be sporting in the water, which it agitated violently and lashed into a foam. It was erect from the water as one of the piles in the slips, and in the uniformity of its diameter I would judge its measure to be from 14 to 16 inches. Its height above the surface of the water was ten to fifteen feet. The head resembled that of a lizard or bullfrog, and was dazzling black, while the throat was pure white. From the head, just above a lizard shaped mouth protruded an inch or more a pair of deep black eyes, half as large as ordinary saucers. The body, or so much as I saw was striped in harmonious shades of black and brown, on the back and sides, the stripes running lengthwise, while the belly was almost white. Running down the center of the back was plain to be seen a sort of fin-like ruffle, about four inches in width.

In another very odd account from the same article, a drug store owner named Winston G. Dinsmore also saw something huge in the bay swimming along near Long Bridge as well, of which he said:

Its head was raised about four feet out of the water, and at intervals be could see a curvature in its huge body at a distance not less than twenty five or thirty feet from its head.

In the following decade there was another notable report from 1885, in an article printed in the March 28 edition of the San Francisco Chronicle. According to the account, a witness named J.P. Allen had been standing on the deck of a ferry traveling between Alameda and Goat Island, now called Yerba Buena Island, with a few others when they saw something they could not explain. The encounter would be described in the newspaper account as follows:

A huge black monster suddenly raised its head and neck from the water to a height of about 10 feet, open its jaws, displaying a mouth two feet wide filled with rows of sharply pointed teeth, and after taking a curious glance at the passing steamer plunged again into the water, at the same time elevating a sixty-foot tail, with which it thrashed the water for some time, after which it made off in the direction of the Alameda baths, near which some fishing boats were anchored. Some incredulous persons to whom the story was told say that the ferryboat struck a floating spar, forcing one end downward in the water and elevating the other as the steamer passed over the submerged end, and that after the steamer had passed the elevated end fell back into the water with a splash.

Amazingly, there was also another separate sighting and apparent capture of a mysterious creature in the bay on the same day as this sighting. On this occasion two men named Carl Sevening and John Peat were out rowing near a place called the North Heads when they were charged by a strange creature with a “a fiercely mustached head of a shape between that of a seal and a sea lion.” The creature allegedly came up under the boat and lifted it up out of the water, nearly capsizing it, before Peat sprung into action. According to a report at the time from the New York Times:

Peat dealt a blow on the monster’s head with an oar, knocking it out for a moment, and Sevening followed with another blow which knocked the beast silly. The pair then secured the animal with the boat’s painter and began towing it, when the enemy came to time for a second round. This it began by towing the boat rapidly for a quarter of a mile. It then came to the surface for breath, when Sevening landed it a blow, gaining first blood, and ending the fight with a square knock-out. The enemy turned belly up and was towed to the foot of Larkin street, where it took six men to land it. The animal measured 6 feet in length and weighed about 300 pounds. It had green eyes and a long, white, bristling mustache. It had two flippers of great strength, which measured 1 1/2 feet in length. The capture will be kept at the foot of Larkin street until noon today.

This seems to be much different in description to what was seen in the Allen report, so just what is going on here? Two different sea monsters in San Francisco Bay at around the same time? Did they really capture it and what was it? Where did its body go? It is a frustrating account in that we will probably never know. Sightings of sea monsters in San Francisco Bay continued into later years, with a report from August 30, 1976, when an artist and minister named Tom D’Onofrio saw one while out riding a horse along Agate Beach, in Bolinas. He says that he rode up the beach and met a friend, Dick Borgstrom, who he talked with for some time before a disturbance in the water drew their attention. The witness would say:

Suddenly, 150 feet from shore, gamboling in an incoming wave, was this huge dragon, possibly 60 feet long and 15 feet wide. . . . the serpent seemed to be playing in the waves, threshing its tail. We were so overpowered by the sight, we were rooted to the spot for about 10 minutes. I literally felt as if I was in the presence of God. My life has been changed since.

The 1980s saw numerous sightings of a strange marine beast in the waters of San Francisco Bay. One of the most well-publicized was a report from October 31, 1983, when a construction crew of five members working right by the Golden Gate Bridge on Route 1 saw a massive creature in the water from a vantage point near Stinson Beach. The creature was described as being around 100 feet long, five feet in diameter, black in color, with a smallish, horse-like head, three coils or humps, and a long neck. The bizarre creature was swimming along near the cliffs while thrashing its head around, and an odd detail is that the monster was apparently trailed by a contingent of sea birds and around two dozen sea lions. A passing truck driver saw it as well, saying it was like a gigantic eel. Indeed, between the years of 1985 and 1987 there were at least eight reports of a sea serpent in San Francisco Bay and its vicinity.

There was a very well-known series of sightings made beginning in 1985 by a pair of brothers named Bill and Bob Clark. They first saw it in February of 1985, when they were watching sea lions swimming about in the bay along the shore side walkway at Marina Green in San Francisco. They say that as they watched the sea lions cavort about, an enormous, long-necked monster “like a plesiosaur” surged up out of nowhere to try and catch one of the animals. One of the witnesses would say:

When it got within a few yards of the group of sea lions it suddenly raised its head and a portion of its body approximately 10 feet straight up out of the water and then it lunged forward into the group of sea lions. We could see the creature create several vertical undulations in its neck as it swam through the water. Then it went underwater. The sea lions swam right in front of us leaping in and out of the water in an attempt to escape the creature. We didn't know it until the next day when we examined the area at low tide but the sea lions swam over a ledge with rocks on it that protruded 20 yards into the bay. The water went from 40 feet deep to only 3 feet deep above the ledge. Suddenly, 20 yards in front of us we saw what looked like half a truck tire break the surface with a long neck and head just under the surface of the water in front of it.


A second arch broke the surface of the water behind the first and then we watched what we thought was a huge black snake swim by but when we expected it to end it got wider. Then there was a splash and a crashing sound as it stopped dead in the water. Immediately, we saw it lift its neck quickly out of the water and it pulled itself backwards to get off the rocks. It splashed back into the water and disappeared. Instantaneously, the rest of the neck came out of the water in a corkscrewing manner as it tried to pull itself off the rocks and into the deeper water. As it corkscrewed it exposed the midsection and the underbelly above the water and we got an excellent view. the midsection had hexagonal scales that did not overlap but were connected to each with a common side. They varied in size from the size of a dime to the size of a silver dollar.

The stunned men sat and watched this otherworldly monster dash about chasing the sea lions, to the point that some of the animals were trying to get up on shore, all of this happening right in front of the startled witnesses. The brothers would claim to see the thing seven more times in the following years. In one of their more notable sightings, the brothers saw the creature again in 2004, this time from an elevated observation point at Fort Mason looking out toward Alcatraz Island. On this occasion, they were able to film the odd creature, the footage of which you can see here. The video is taken from quite a long distance off, but seems to show something rather unusual maneuvering about in the water, and analysis done by Clifford Paiva, of BSM Research Associates in California City, determined it to be “an unidentified group of marine animals operating in the San Francisco Bay," and the Clark brothers have said of their experiences and footage:

We have had several sightings of sea serpents in San Francisco Bay since 1985. On February 5, 1985 we saw a sea serpent beach itself only 20 yards from where we were parked in our car and we saw the entire animal expect the tail. On January 26, 2004 we took a 3 1/2 minute video which we claim contains images of several sea serpents swimming in SF Bay. We had 2 independent analyses of the video done. One was done by BSM Associates (expert image analyst Clifford Paiva and physicist Dr. Harold Slusher) and the second was done by marine biologist Bruce Champagne. Both analyses concluded that our video contains images of several large unknown serpentine marine animals swimming in SF Bay. We invite all skeptics to provide us with the expert of their choice who is willing to do an in-depth analysis of our video and we will send them a free copy. We only request that they agree not to post any portion of the video on the internet or anywhere else without our permission and if the conclusion of their analysis disagrees with the Paiva/Slusher analysis and the Champagne analysis that they provide us with their supporting documentation.

These sightings were to launch an obsession with them, and the two have ever since delved into reports of anything unusual swimming about in the bay, and indeed many of the most compelling reports are ones that they have dug up. One such account comes from a former Marine Corps pilot, who told them:

I travel between Sacramento and San Francisco several times a month. On my way back from San Francisco early this afternoon on the Carquinez Bridge, I noticed a curious black object in the water just west of the bridge. I was driving east bound and looking to my left and I could see underneath and slightly west of the west bound bridge when I noticed the object. It was black, not shiny but not dull, either. It was sort of hump shaped. Understand that I only caught sight of this object for several seconds as I was driving away from it, now looking back over my left shoulder. In those several seconds I observed the following.


The object was black, smooth, and hump shaped. Hard to judge size as there was nothing man made near it but I would estimate the object to be approximately 4’ long and 2-3’ wide. The object did not seem to be moving. It slowly sank vertically out of sight in the few seconds I observed it. I noticed no horizontal movement, no splashing, no wake. I have seen porpoise and whales but never in the Straight and they are typically a grey or dark grey in color. There was no dorsal fin. The water was fairly calm and there were no ships or boats in the straight. No wake was evident. The day was partly sunny and warm. It was about 1:15 PM. I am fairly certain what I saw was not any sea mammal I am familiar with. I don’t really know what I saw but it was very strange, especially so close to the bridge.

A still from the Clark footage

Another curious account comes from the site Cryptomundo, where a witness claimed to have seen the beast in 2007. According to her:

My husband and I live in the Candlestick Point condos off the 101 and saw the sea serpent twice in the summer of 2007. I saw it first while driving alone. It was undulating in and out of the water and I could clearly see what looked like several humps moving. We last saw it in August 2007. My husband saw it eat a pelican sitting in the water and those birds are huge. (This occurred) as I was driving and trying to watch the road. I didn’t see it happen, but immediately after we both witnessed a bunch of pelicans wildly dive-bombing the serpent in the water as if on the attack.

Yet another witness saw the creature in the bay in 2009, which she said looked like a giant black snake with it head and neck lifted about 6 feet from the surface of the water. Behind it were four “arches,” or coils. even more recent still was a report collected by the Clarks of a witness in 2013, who says he saw it at at Baker Beach, just south of the Golden Gate Bridge. These sorts of sightings leave us to wonder just what it is that is dwelling in the depths of San Francisco Bay. What could these creatures be, and how many types of beasts are we dealing with here? Why are they there? Are they there to feed off of the sea lions, as the Clark report seems to suggest, or are they just passing through? No one knows, but it is certainly something to keep an eye out for the next time you are in the area, that's for sure.

Brent Swancer

Brent Swancer is an author and crypto expert living in Japan. Biology, nature, and cryptozoology still remain Brent Swancer’s first intellectual loves. He's written articles for MU and Daily Grail and has been a guest on Coast to Coast AM and Binnal of America.

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